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Low hot water pressure?

I have low water pressure on all of my hot fixtures for the last few days. This happened about month ago, but seemed to fix itself. I have turned the suppy on and off, turned the gas on and off, with no results. Our gas hot water heater is only one year old.

Re: Low hot water pressure?

Re: Low hot water pressure?

Here's my SWAG for your problem based on that it is intermittent and affects all faucets. You have a gate valve in the inlet pipe (cold water pipe) to the water heater. Its there to allow the water heater to be changed/services without shutting off cold water to the rest of the house. The rubber seal has deteriorated and come loose and is partially blocking the water going into the water heater.

It should be an easy fix, you shut off the water to the whole house. You use a wrench to remove the stem from the gate valve and you replace the rubber washer at the bottom of the stem, then reassemble. At this age, you might need to replace the stem washer/seal as well.

Re: Low hot water pressure?

Originally Posted by keith3267

Here's my SWAG for your problem based on that it is intermittent and affects all faucets. You have a gate valve in the inlet pipe (cold water pipe) to the water heater. Its there to allow the water heater to be changed/services without shutting off cold water to the rest of the house. The rubber seal has deteriorated and come loose and is partially blocking the water going into the water heater.

It should be an easy fix, you shut off the water to the whole house. You use a wrench to remove the stem from the gate valve and you replace the rubber washer at the bottom of the stem, then reassemble. At this age, you might need to replace the stem washer/seal as well.

Gate valves don't have rubber washers. They have a brass gate that closes off the water. That's the reason they call them gate valves.

Re: Low hot water pressure?

Originally Posted by HoustonRemodeler

Make sure they are pointed in the right direction. If in doubt, replace them.

Houston what are you referring to? There is no direction on gate valves. The only valve that has direction is a stop and waste valve and that is just to drain the line after the valve using the bleeder cap on the side of the valve.

Re: Low hot water pressure?

I think that Keith was talking about the rubber washer in the flex from the gate valve to the water heater. But I don't think that a broken, chewed up washer on the cold side, can cause a problem like the OP has. What it can cause, is a leak. But it won't hurt to check those washers.

Measure the water pressure in various spots around the house at different times during the day, hot and cold, write them down, and tell us your findings. I won't rule out the water pressure reducer.

Re: Low hot water pressure?

My bad, I meant Globe Valve. In teaching, there is a rule called the Law of Primacy. It means that if you accidently learn something wrong, the first time you learn about that subject, it will always stick with you. The first time I picked up a globe valve, it was mis-labeled as a gate valve and that has stuck with me ever since. I'll try to be more careful in the future.